Dynamic TryParse for all data types

Question

I have the need to examine to see if an object can be converted to a specific DataType or not, and came up with this :

public static bool TryParseAll(System         


        

Answer 1

Here is my version of generic TryParse method. I believe you can use this version too:

double pi;
if(ValueTypeHelper.TryParse("3.14159", out pi)) {
    // .. pi = 3.14159
}
...
string eStr = "2.71828";
float e;
if(eStr.TryParse(out e)) {
    // .. e = 2.71828f
}
...
static class ValueTypeHelper {
    static IDictionary cache = new Dictionary();
    public static bool TryParse(this string valueStr, out T result) {
        Delegate d = null;
        if(!cache.TryGetValue(typeof(T), out d)) {
            var mInfos = typeof(T).GetMember("TryParse", MemberTypes.Method, BindingFlags.Static | BindingFlags.Public);
            if(mInfos.Length > 0) {
                var s = Expression.Parameter(typeof(string));
                var r = Expression.Parameter(typeof(T).MakeByRefType());
                d = Expression.Lambda>(
                    Expression.Call(mInfos[0] as MethodInfo, s, r), s, r).Compile();
            }
            cache.Add(typeof(T), d);
        }
        result = default(T);
        TryParseDelegate tryParse = d as TryParseDelegate;
        return (tryParse != null) && tryParse(valueStr, out result);
    }
    delegate bool TryParseDelegate(string valueStr, out T result);
}